xref: /openbmc/linux/drivers/soc/ti/k3-socinfo.c (revision c5c87812)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * TI K3 SoC info driver
4  *
5  * Copyright (C) 2020 Texas Instruments Incorporated - http://www.ti.com
6  */
7 
8 #include <linux/mfd/syscon.h>
9 #include <linux/of.h>
10 #include <linux/of_address.h>
11 #include <linux/regmap.h>
12 #include <linux/platform_device.h>
13 #include <linux/slab.h>
14 #include <linux/string.h>
15 #include <linux/sys_soc.h>
16 
17 #define CTRLMMR_WKUP_JTAGID_REG		0
18 /*
19  * Bits:
20  *  31-28 VARIANT	Device variant
21  *  27-12 PARTNO	Part number
22  *  11-1  MFG		Indicates TI as manufacturer (0x17)
23  *  1			Always 1
24  */
25 #define CTRLMMR_WKUP_JTAGID_VARIANT_SHIFT	(28)
26 #define CTRLMMR_WKUP_JTAGID_VARIANT_MASK	GENMASK(31, 28)
27 
28 #define CTRLMMR_WKUP_JTAGID_PARTNO_SHIFT	(12)
29 #define CTRLMMR_WKUP_JTAGID_PARTNO_MASK		GENMASK(27, 12)
30 
31 #define CTRLMMR_WKUP_JTAGID_MFG_SHIFT		(1)
32 #define CTRLMMR_WKUP_JTAGID_MFG_MASK		GENMASK(11, 1)
33 
34 #define CTRLMMR_WKUP_JTAGID_MFG_TI		0x17
35 
36 static const struct k3_soc_id {
37 	unsigned int id;
38 	const char *family_name;
39 } k3_soc_ids[] = {
40 	{ 0xBB5A, "AM65X" },
41 	{ 0xBB64, "J721E" },
42 	{ 0xBB6D, "J7200" },
43 };
44 
45 static int
46 k3_chipinfo_partno_to_names(unsigned int partno,
47 			    struct soc_device_attribute *soc_dev_attr)
48 {
49 	int i;
50 
51 	for (i = 0; i < ARRAY_SIZE(k3_soc_ids); i++)
52 		if (partno == k3_soc_ids[i].id) {
53 			soc_dev_attr->family = k3_soc_ids[i].family_name;
54 			return 0;
55 		}
56 
57 	return -EINVAL;
58 }
59 
60 static int k3_chipinfo_probe(struct platform_device *pdev)
61 {
62 	struct device_node *node = pdev->dev.of_node;
63 	struct soc_device_attribute *soc_dev_attr;
64 	struct device *dev = &pdev->dev;
65 	struct soc_device *soc_dev;
66 	struct regmap *regmap;
67 	u32 partno_id;
68 	u32 variant;
69 	u32 jtag_id;
70 	u32 mfg;
71 	int ret;
72 
73 	regmap = device_node_to_regmap(node);
74 	if (IS_ERR(regmap))
75 		return PTR_ERR(regmap);
76 
77 	ret = regmap_read(regmap, CTRLMMR_WKUP_JTAGID_REG, &jtag_id);
78 	if (ret < 0)
79 		return ret;
80 
81 	mfg = (jtag_id & CTRLMMR_WKUP_JTAGID_MFG_MASK) >>
82 	       CTRLMMR_WKUP_JTAGID_MFG_SHIFT;
83 
84 	if (mfg != CTRLMMR_WKUP_JTAGID_MFG_TI) {
85 		dev_err(dev, "Invalid MFG SoC\n");
86 		return -ENODEV;
87 	}
88 
89 	variant = (jtag_id & CTRLMMR_WKUP_JTAGID_VARIANT_MASK) >>
90 		  CTRLMMR_WKUP_JTAGID_VARIANT_SHIFT;
91 	variant++;
92 
93 	partno_id = (jtag_id & CTRLMMR_WKUP_JTAGID_PARTNO_MASK) >>
94 		 CTRLMMR_WKUP_JTAGID_PARTNO_SHIFT;
95 
96 	soc_dev_attr = kzalloc(sizeof(*soc_dev_attr), GFP_KERNEL);
97 	if (!soc_dev_attr)
98 		return -ENOMEM;
99 
100 	soc_dev_attr->revision = kasprintf(GFP_KERNEL, "SR%x.0", variant);
101 	if (!soc_dev_attr->revision) {
102 		ret = -ENOMEM;
103 		goto err;
104 	}
105 
106 	ret = k3_chipinfo_partno_to_names(partno_id, soc_dev_attr);
107 	if (ret) {
108 		dev_err(dev, "Unknown SoC JTAGID[0x%08X]\n", jtag_id);
109 		ret = -ENODEV;
110 		goto err_free_rev;
111 	}
112 
113 	node = of_find_node_by_path("/");
114 	of_property_read_string(node, "model", &soc_dev_attr->machine);
115 	of_node_put(node);
116 
117 	soc_dev = soc_device_register(soc_dev_attr);
118 	if (IS_ERR(soc_dev)) {
119 		ret = PTR_ERR(soc_dev);
120 		goto err_free_rev;
121 	}
122 
123 	dev_info(dev, "Family:%s rev:%s JTAGID[0x%08x] Detected\n",
124 		 soc_dev_attr->family,
125 		 soc_dev_attr->revision, jtag_id);
126 
127 	return 0;
128 
129 err_free_rev:
130 	kfree(soc_dev_attr->revision);
131 err:
132 	kfree(soc_dev_attr);
133 	return ret;
134 }
135 
136 static const struct of_device_id k3_chipinfo_of_match[] = {
137 	{ .compatible = "ti,am654-chipid", },
138 	{ /* sentinel */ },
139 };
140 
141 static struct platform_driver k3_chipinfo_driver = {
142 	.driver = {
143 		.name = "k3-chipinfo",
144 		.of_match_table = k3_chipinfo_of_match,
145 	},
146 	.probe = k3_chipinfo_probe,
147 };
148 
149 static int __init k3_chipinfo_init(void)
150 {
151 	return platform_driver_register(&k3_chipinfo_driver);
152 }
153 subsys_initcall(k3_chipinfo_init);
154